Unauthorized persons utilizing office telephones to make personal phone calls has always been a problem. Most of this unauthorized use occurs after normal business hours when office personnel are not present to see who is utilizing the telephones.
In order to protect against unauthorized telephone calls, a number of mechanical security devices are available. Thus, the familiar dial lock prevents the dialing mechanism on a dial type telephone from being rotated. For use on a desk style Touch Tone set, a device is available which covers the pushbuttons, thus preventing the user from keying in a number. Another locking device available for use on desk style phones, including both dial and Touch Tone types, is that described in U.S. Pat. No. 3,712,964, issued Jan. 23, 1973. This device prevents both outgoing and incoming calls by holding the switch pins down and thus keeping the telephone electrically inactive.
Although at least one of the above devices will at least partially protect all types of standard desk style phones and all styles of phones having rotary dials, they cannot be used on "Call Director" style Touch Tone units. Call-Director style telephones are those having the handset mounted on one side of the base, and normally have multiple pushbuttons for switching between multiple incoming/outgoing lines. Call-Director style phones may include either a Touch Tone or rotary dialing capability. Often, however, Call-Director style phones are ordered with a dial rather than the Touch Tone feature because of the inability to electrically secure the Touch Tone type units.
It is the general object of the present invention to provide a telephone lock for use on Call-Director-style telephone receivers.
It is another object of the present invention to provide a telephone lock for Call-Director-style telephones which keeps the telephone electrically inactive.
It is a further object of the present invention to provide a cradle lock for Call-Director-style receivers which prevents outgoing calls and incoming collect calls.
It is still another object of the present invention to provide an inexpensive telephone lock for use on both dial and Touch Tone type Call-Director-style transceivers.
The above and other objects, features and advantages of the present invention will become more apparent from the detailed description of the preferred embodiment when read in conjunction with the drawings.